Vertical jump: Lawrence Okoye > Tavon Austin

The 49ers’ rookies arrived Thursday in advance of their three-day minicamp and the most intriguing of the arrivals wasn’t one of their 11 draft picks. The Man of Mystery, of course, is free agent defensive lineman Lawrence Okoye, 21, the British record holder in the discus who has never played football.

Lawrence Okoye. (AP)

Okoye’s unique journey officially begins Friday, three months after he left south London and began football training in Hiram, Ga. The 49ers’ practices will be open to the media Friday and Saturday and plenty of eyes will be trained on Okoye, a 6-foot-6, 304-pound “Adonis” (Jim Harbaugh’s word) with eye-popping athleticism.

At the NFL Super Regional Combine in Dallas last month, Okoye’s vertical jump (35 inches) bettered the leaps posted by 21 of 34 wide receivers at the combine (No. 8 pick Tavon Austin had a 32-inch vertical). In addition, his broad jump (10-5) would have ranked second among the 32 running backs at the combine. Finally, Okoye’s 40-yard dash (4.74) nearly equaled the 4.72 posted by one of his new teammates, Pro Bowl wideout Anquan Boldin, at the 2003 combine.

How would Okoye have ranked among guys his own size – the defensive linemen — at the NFL combine?

The numbers are below. It’s worth noting that the majority of linemen who posted better marks than Okoye in the broad jump, vertical jump and 40-yard dash are college defensive ends who will transition to outside linebacker in the NFL. That is, they weigh about 40 pounds less than Okoye. With that in mind, I also included the best mark by a lineman who weighs at least 280 pounds in each of the events.

Okoye is clearly a physical marvel. But can he become a football player? We’ll get our first glimpse during Friday’s non-padded practice:

It remains to be seen whether Okoye can make an NFL roster – let alone become an effective pass-rusher. But he does measure up with the aforementioned trio in one area. Here’s a look at how Watt, Smith, Miller and Okoye fared in their pre-draft workouts (the measurements and results of Watt, Smith and Miller are from the 2011 NFL combine):

J.J. WATT, DE, TEXANS

6-5, 290

40-yard dash: 4.81

Vertical jump: 37 inches

Broad jump: 10-0

Bench press: 34 reps of 225 pounds

***********************************************

ALDON SMITH, LB, NINERS

6-4, 263

40-yard dash: 4.74

Vertical jump: 34 inches

Broad jump: 9-10

Bench press: 20

***********************************************

VON MILLER, LB, BRONCOS

6-3, 246

40-yard dash: 4.42

Vertical jump: 37 inches

Broad jump: 10-6

Bench press: 21

***********************************************

LAWRENCE OKOYE, DL, NINERS

6-6, 304

40-yard dash: 4.74

Vertical jump: 35 inches

Broad jump: 10-5

Bench press: 30

***********************************************

Here’s the feature story on Okoye from Friday’s Chronicle. Said former Cowboys personnel executive Gil Brandt of Okoye’s workout at the NFL Super Regional Combine: “He looked like Secretariat next to a bunch of plow horses.”